Oops! Thanks a lot! Jean
On 29 October 2015 at 15:45, Adams, Jean <jvad...@usgs.gov> wrote: > If you read the help file for optimize, you will see that you need to set > the argument maximum to TRUE. > > ?optimize > > optimize(sm, c(0, 50), maximum=TRUE) > > Jean > > On Thu, Oct 29, 2015 at 4:19 PM, Jianling Fan <fanjianl...@gmail.com> wrote: >> >> Hello, everyone, >> >> I have a specific equation, When I draw it out, I found there is a >> max. value for it at about x=5. but I couldn't point it out by >> optimize(). Does anyone know why? Thanks! >> >> my code is: >> >> d50<-18.04 >> c<- -1.276 >> dm<-147 >> >> sm <- function (x) { >> >> 1/(1+(x/d50)^c)+(1-1/(1+(dm/d50)^c))*x/dm-(1/(1+((x-1)/d50)^c)+(1-1/(1+(dm/d50)^c))*(x-1)/dm) >> } >> curve(sm, 0,50) >> optimize(sm,c(0,50)) >> >> The optimize() only give min. value but not max. >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide >> http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. > > -- Jianling Fan 樊建凌 ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.